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Related papers: Modeling the Void H I Column Density Spectrum

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Using the model for (bottom-up) hierarchical halo growth recently developed by Salvador-Sol\'e et al. (2012), we derive the typical spherically averaged density profile for haloes with several relevant masses in the concordant warm dark…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-10 Jordi Viñas , Eduard Salvador-Solé , Alberto Manrique

Properties of $\sim$ 6 000 Ly-$\alpha$ absorbers observed in 19 high resolution spectra of QSOs are investigated using the model of formation and evolution of DM structure elements based on the Zel'dovich theory. This model asserts that…

Astrophysics · Physics 2009-11-11 M. Demianski , A. G. Doroshkevich , V. I. Turchaninov

We present the first $z=0$ HI column density distribution function, $f(N_\mathrm{HI})$, extending down to $\log (N_\mathrm{HI}/\mathrm{cm}^{-2})=17.8$. This was derived from high-sensitivity 21-cm emission-line imaging at $\sim$1 kpc…

Wave Dark Matter (WaveDM) has recently gained attention as a viable candidate to account for the dark matter content of the Universe. In this paper we explore the extent to which dark matter halos in this model, and under what conditions,…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-08 Antonio Herrera-Martín , Martin Hendry , Alma X. Gonzalez-Morales , L. Arturo Ureña-López

Light scattering at near-infrared wavelengths has been used to study the optical properties of the interstellar dust grains, but these studies are limited by the assumptions on the strength of the radiation field. On the other hand, thermal…

Astrophysics of Galaxies · Physics 2021-03-24 M. Saajasto , M. Juvela , C. Lefevre , L. Pagani , N. Ysard

Obscured AGNs provide an opportunity to study the material surrounding the central engine. Geometric and physical constraints on the absorber can be deduced from the reprocessed AGN emission. In particular, the obscuring gas may reprocess…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Raj Gohil , David R. Ballantyne

We aim at analysing systematically the distribution and physical properties of neutral and mildly ionised gas in the Milky Way halo, based on a large absorption-selected data set. Multi-wavelength studies were performed combining optical…

Astrophysics of Galaxies · Physics 2015-06-04 N. Ben Bekhti , B. Winkel , P. Richter , J. Kerp , U. Klein , M. T. Murphy

We examine the statistics of the low-redshift Ly-alpha forest in an adaptive mesh refinement hydrodynamic cosmological simulation of sufficient volume to include distinct large-scale environments. We compare our HI column density…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 Stephanie Tonnesen , Britton D. Smith , Juna Kollmeier , Renyue Cen

We study the evolution of the galaxy UV luminosity density as a function of redshift in the Hubble Deep Field North (HDF-N). We estimate the amount of energy absorbed by dust and hidden from optical observations by analyzing the HDF-N…

Astrophysics · Physics 2016-08-30 M. Massarotti , A. Iovino , A. Buzzoni

In this paper, we formulate a new model of density distribution for halos made of warm dark matter (WDM) particles. The model is described by a single microphysics parameter - the mass (or, equivalently, the maximal value of the initial…

Astrophysics of Galaxies · Physics 2019-08-30 A. Rudakovskyi , D. Savchenko

Recent modeling of the warm absorber in active galactic nuclei has proved the usefulness of constant total (gas plus radiation) pressure models, which are highly stratified in temperature and density. We explore the consistency of those…

Astrophysics · Physics 2009-11-13 L. Chevallier , B. Czerny , A. Rozanska , A. C. Goncalves

We present a survey for optically thick Lyman limit absorbers at z<2.6 using archival Hubble Space Telescope observations with the Faint Object Spectrograph and Space Telescope Imaging Spectrograph. We identify 206 Lyman limit systems…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Joseph Ribaudo , Nicolas Lehner , J. Christopher Howk

We list and analyze H I absorption lines at redshifts 2 < z < 4 with column density (12 < log(N_HI) < 19) in 40 high-resolutional (FWHM = 8.0 km/s) quasar spectra obtained with the Keck+HIRES. We de-blend and fit all H I lines within 1,000…

Astrophysics · Physics 2008-11-26 T. Misawa , D. Tytler , M. Iye , D. Kirkman , N. Suzuki , D. Lubin , N. Kashikawa

A model of Lyman limit QSO absorption systems is investigated where they are produced in gaseous galactic halos with a two-phase structure: a hot phase at the halo virial temperature in approximate pressure equilibrium, and a cold,…

Astrophysics · Physics 2009-10-28 H. J. Mo , J. Miralda-Escude

We present an analysis of the molecular hydrogen absorption system at z$_{\rm abs}$ = 2.811 in the spectrum of the blazar Q0528-250. We demonstrate that the molecular cloud does not cover the background source completely. The partial…

Astrophysics of Galaxies · Physics 2015-02-17 V. V. Klimenko , S. A. Balashev , A. V. Ivanchik , C. Ledoux , P. Noterdaeme , P. Petitjean , R. Srianand , D. A. Varshalovich

The halo mass function, dn/dM, predicted by hierarchical clustering models can be measured indirectly using dynamical probes like the distribution of gravitational lens image separations, dn/dDelta-theta, or halo circular velocities, dn/d…

Astrophysics · Physics 2009-08-18 C. S. Kochanek , Martin White

With high resolution (0.46kpc/h), adaptive mesh-refinement Eulerian cosmological hydrodynamic simulations we compute properties of O VI and O VII absorbers from the warm-hot intergalactic medium (WHIM). Our new simulations are in broad…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Renyue Cen

%methods {We used the EMIR receiver and FTS spectrometer at the IRAM 30m to construct absorption spectra toward bright extra-galactic background sources at 195 kHz spectral resolution ($\approx$ 0.6 \kms). We used the IRAM Plateau de Bure…

Astrophysics of Galaxies · Physics 2015-06-19 H. Liszt , J. Pety , M. Gerin , R. Lucas

We perform a systematic study of physical properties and distribution of neutral and ionised gas in the halo of the Milky Way (MW). Beside the large neutral intermediate- and high-velocity cloud (IVC, HVC) complexes there exists a…

Astrophysics of Galaxies · Physics 2010-07-21 N. Ben Bekhti , P. Richter , B. Winkel , J. Kerp , P. Kalberla , U. Klein , M. T. Murphy

We investigate the metallicity evolution and content of the intergalactic medium (IGM) and galactic halo gas from z=2->0 using 110-million particle cosmological hydrodynamic simulations. We focus on the detectability and physical properties…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Benjamin D. Oppenheimer , Romeel Davé , Neal Katz , Juna A. Kollmeier , David H. Weinberg
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